#include <iostream>
#include <cstring>
#include <string>
#include <unistd.h>
#include <pthread.h>

int tickets = 1000;
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t cond = PTHREAD_COND_INITIALIZER;

void* start_routine(void* args)
{
    std::string name = static_cast<const char*>(args);
    while(true)
    {
        pthread_mutex_lock(&mutex);
        pthread_cond_wait(&cond, &mutex);//为什么要有mutex,后面再说
        //判断暂时省略
        std::cout << name << "->" << tickets << std::endl;
        tickets--;
        pthread_mutex_unlock(&mutex);
    }
}

int main()
{
    //通过条件变量控制线程的执行
    pthread_t t[5];
    for(int i = 0; i < 5; ++i)
    {
        char* name = new char[64];
        snprintf(name, 64, "thread %d", i + 1);
        pthread_create(t + i, nullptr, start_routine, name);
    } 

    while(true)
    {
        sleep(2);
        //pthread_cond_signal(&cond);
        pthread_cond_broadcast(&cond);
        std::cout << "main thread wakeup one thread ..." << std::endl;
    }

    for(int i = 0; i < 5; ++i)
    {
        pthread_join(t[i], nullptr);
    } 

    return 0;
}